Longitudinal analysis of the recovery of trunk control and upper extremity following stroke: An individual growth curve approach

ABSTRACT

Background and Purpose

Trunk control is thought to contribute to upper extremity function. It is unclear whether recovery of trunk control has an impact on the recovery of the upper extremity in people with stroke. This longitudinal study monitored the recovery of trunk control and upper extremity in the first 6 months following stroke.

Methods

Forty-five participants with stroke were assessed monthly for 6 months following stroke. Trunk control was assessed using the Trunk Impairment Scale (TIS); upper extremity impairment and function were assessed with the Fugl-Meyer (FMA) and Streamlined Wolf Motor Function Test (SWMFT) respectively. The SWMFT included the performance time (SWMFT-Time) and functional ability scale (SWMFT-FAS). The individual growth curve modeling was used to analyze the longitudinal data.

Results

The recovery curve of TIS, FMA, SWMFT-Time and SWMFT-FAS followed a quadratic trend, with the rate of recovery decreasing from the first to sixth month. As TIS score improved over time, FMA, SWMFT-Time and SWMFT-FAS improved in parallel with the TIS score. TIS at each time point was found to be a significant predictor of FMA, SWMFT-Time and SWMFT-FAS at 6 months post stroke.

Conclusion

Our work has provided, for the first time, substantial evidence that the pattern of recovery of trunk control is similar to that of the recovery of upper extremity following stroke. In addition, this study provides evidence on which to design a prospective study to evaluate whether improvement in trunk control early post-stroke results in better long-term upper extremity function.

KEYWORDS:

• Trunk control
• upper extremity
• recovery trajectory
• stroke
• neurorehabilitation

Acknowledgments

We wish to thank Mr. Joshua Guo Xian Wong, biostatistician of Tan Tock Seng Hospital, Singapore, and Dr. Sean Ewings, statistician of the Southampton Statistical Sciences Research Institute, University of Southampton, United Kingdom, for their kind assistance and constructive advice on statistical analysis for this study.

Additional information

Funding

The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article:Seng Kwee Wee would like to acknowledge Tan Tock Seng Hospital, Singapore, for funding his PhD study at the University of Southampton, United Kingdom.